Always pay attention and double-check the camera settings. Always pay attention and double-check the camera settings. I should repeat the sentence a third time, but I think I got the message. I shot these images at a shutter speed of 1/4000th of a second, with the aperture set at F5.6 or F8. Even on a bright day, that is not enough light to give a good exposure. I thought I was in aperture priority. The 1/4000 shutter speed setting is next to the aperture priority setting on the Nikon FM3a.